盐度和加曲量对罗非鱼片加工废弃物速酿鱼露的影响

对罗非鱼片加工废弃物速酿鱼露的发酵工艺进行了初步研究,从氨基酸态氮、总酸、TVBN、色度、感官5个指标分析了速酿鱼露在不同盐度(4,7,10,13 g/dL)和不同加曲量(质量分数10%、15%、25%、35%)下的发酵状况,综合各指标的影响确定适宜的速酿发酵条件为:7 g/dL盐度和10%的加曲量,在此条件下的鱼露发酵液氨基酸态氮、总酸含量较高、腐败程度低,风味感官评价较好.

鲢鱼露发酵工艺的研究

以发酵温度 35℃、4 0℃和 4 5℃ ,加曲量 4 0 %、2 0 %和 10 % ,加盐量 10 %、14%和18%作为L9(34)正交试验的因素与水平 ,考察其对鱼露氨基酸生成率及鱼露综合质量的影响。结果表明 ,温度对氨基酸生成率有一定影响 ,对鱼露综合质量的影响极显著 ;加盐量对氨基酸生成率有显著影响 ,对鱼露综合质量有极显著影响 ,随着加盐量减少 ,氨基酸生成率和鱼露综合质量都明显增加 ;当加曲量达到 10 %后再增大加曲量 ,对氨基酸生成率及鱼露综合质量的影响都不显著。氨基酸生成率最高的工艺条件为温度 35℃、加盐量 10 %、加曲量为10 %～ 4 0 % ;鱼露综合质量最好的工艺条件为温度 4 5℃、加盐量 10 %、加曲量为 10 %～4 0 % ;最后 ,确定鱼露的速酿最佳工艺条件为温度 4 5℃、加盐量 10 %、加曲量为 4 0 %

Application of response surface methodology in optimization of bioleaching parameters for high-magnesium nickel sulfide ore

The response surface methodology(RSM)was used to optimize the operating parameters during the bioleaching of Jinchuan high-magnesium nickel sulfide ore.The particle size,acid addition,pulp density and inoculation amount were chosen as the investigated parameters.To maximize the leaching efficiency of nickel,copper,cobalt and minimize the dissolution of magnesium and iron ions,the model suggested a combination of optimal parameters of particles less than 0.074 mm being 72.11%,sulfuric acid addition being 300 kg/t,pulp density being 5%and inoculation amount being 12.88%.Under the conditions,the average results of three parallel experiments were 89.43%of nickel leaching efficiency,36.78%of copper leaching efficiency,84.07%of cobalt leaching efficiency,49.19%of magnesium leaching efficiency and 0.20 g/L of iron concentration.The model indicated that the most significant factor in response of the leaching efficiency of valuable metal is the particle size,and the most significant factor in response to the leaching efficiency of harmful ions(Mg2+)is the amount of sulfuric acid addition.And according to the suggested models,no significance of the interaction effect between particle size and acid addition was shown.Under the optimized parameters suggested by models,the valuable metals could be separated from harmful ions during the bioleaching process.

Study of drying of small diameter Larch lumbers with intermittent heating

Intermittent heating for drying of small diameter Larch lumbers is investigated experimentally. The lumbers were dried using an experimental drying schedule. Moisture content (MC) of the lumber was continuously recorded and final drying defects were examined. The drying curves showed that the drying rate was a constant in the early stage of intermittent heating drying and decreased evidently when the MC was about 18% (intermittent 2h) and 20% (intermittent 6h). The drying quality reached the second (intermittent 2h) and first grade (intermittent 6h) of the Chinese National Standard. The visual drying defects, especially the check extent along grains were reduced with intermittent heating. When the intermittent time increased, the effect was more obvious.

R^2 Correction and Its Implication of Present Cosmic Accelerating Behavior

In this work we show an model of the universe in which certain quadratic correction is considered. Our results indicate that the R2 term can act as the present impetus of cosmic acceleration, but there may be a future collapsing universe with this component damped. This model can also tolerate a negative cosmological constant ?, although there seems to be no need for a non-vanishing one. In our simplification, this curvature component has a stationary equation of state, which is similar to radiation. Unlike other dark energy models, this 'missing' energy has a negative density. Some details and effects on cold dark matter and Λ-relevant model have been discussed in the frame of curvature-squared gravity theories.

Plastic characterization of metals by combining nanoindentation test and finite element simulation

Materials with the same elastic modulus E and representative stress and strain （σr,εr） present similar indentation-loading curves, whatever the value of strain hardening exponent n. Based on this definition, a good approach was proposed to extract the plastic properties or constitutive equations of metals from nanoindentation test combining finite element simulation. Firstly, without consideration of strain hardening, the representative stress was determined by varying assumed representative stress over a wide range until a good agreement was reached between the computed and experimental loading curves. Similarly, the corresponding representative strain was determined with different hypothetical values of strain hardening exponent in the range of 0-0.6. Through modulating assumed strain hardening exponent values to make the computed unloading curve coincide with that of the experiment, the real strain hardening exponent was acquired. Once the strain hardening exponent was determined, the initial yield stress ay of metals could be obtained by the power law constitution. The validity of the proposed methodology was verified by three real metals： AISI 304 steel, Fe andA1 alloy.

A morphing machining strategy for artificial bonet

In this work, a novel morphing machining strategy （MMS） is proposed. In the method, the workpiece is progressively carved out from the stock. Pitfalls in conventional iso-height strategy, such as sharp edges and unevenly distributed left-over materials, are overcome. Moreover, to calculate different levels in the MMS, an energy-based morphing algorithm is proposed. Finally, the proposed strategy is employed in the machining of artificial bone represented by a T-spline surface. The excellent properties of T-spline, such as expressing complex shapes with a single surface, have been well adopted to artificial bone fabri- cation. Computer simulation and the actual machining of the middle finger bone show the feasibility of the proposed strategy.

Side-channel attacks and learning-vector quantization

The security of cryptographic systems is a major concern for cryptosystem designers, even though cryptography algorithms have been improved. Side-channel attacks, by taking advantage of physical vulnerabilities of cryptosystems, aim to gain secret information. Several approaches have been proposed to analyze side-channel information, among which machine learning is known as a promising method. Machine learning in terms of neural networks learns the signature （power consumption and electromagnetic emission） of an instruction, and then recognizes it automatically. In this paper, a novel experimental investigation was conducted on field-programmable gate array （FPGA） implementation of elliptic curve cryptography （ECC）, to explore the efficiency of side-channel information characterization based on a learning vector quantization （LVQ） neural network. The main characteristics of LVQ as a multi-class classifier are that it has the ability to learn complex non-linear input-output relationships, use sequential training procedures, and adapt to the data. Experimental results show the performance of multi-class classification based on LVQ as a powerful and promising approach of side-channel data characterization.

A weighted Wilcoxon estimate for the covariate-specific ROC curve

The covariate-specific receiver operating characteristic(ROC) curve is an important tool for evaluating the classification accuracy of a diagnostic test when it is associated with certain covariates. In this paper,a weighted Wilcoxon estimator is constructed for estimating this curve under the framework of location-scale model for the test result. The asymptotic normality is established, both for the regression parameter estimator and the estimator for the covariate-specific ROC curve at a fixed false positive point. Simulation results show that the Wilcoxon estimator compares favorably to its main competitors in terms of the standard error, especially when outliers exist in the covariates. As an illustration, the new procedure is applied to the dementia data from the national Alzheimer's coordinating center.